The Wu experiment — parity violation confirmed

36:32Okay. So so the chemistry is failing, right? All right. Now let's do a physics attempt. >> Okay. >> Okay. Um in in physics we're always talking about something called the right-h hand rule. Okay. Um right-hand rule is how we do crossroducts of vectors and it defines our coordinate system. For example, if you have a wire that's got current moving up, then you put your thumb on your right hand towards the current and then you curl your hand. And the way you curl your hand is the way that the magnetic field is going. >> So, so in this in this image, we're seeing uh someone with a thumbs up hand with this wire going through it. >> And and the the current is going up. So the thumb is pointing up

37:13>> and and there you know you can see the hand the fingernails are point like are in like in the front of the image and so the >> and the way that I curl the fingers the fingers are curled counterclockwise. >> Yes. >> And the and then it's also now flowing in >> the magnetic field is flowing where my fingers fingers are which is yeah that so that's called the right hand rule and we live a right hand we live in a right-handed coordinate system. What that really means is the following. Okay. What that means is if I have my x-axis let's say this way >> and my y ais this way >> then my z-axis is this way. >> So if if I have my x-axis pointing north >> but yeah let's say let's say pointing outward >> outward >> and my y-axis to the left. Yes.

37:54>> Then the z-axis is up >> up. Okay. >> Now somebody who created physics could have easily been left-handed >> right >> and said nah x ais this way >> y ais this way. So z-axis is pointing down. The fact that Z-axis is pointing up here and not down is just a human constru. >> It's a choice that we've made because probably the guy who who made it up, the made up the cross productduct was like, I'm going to use a right-handed coordinate system, right? >> Yes. >> And so our coordinate system is right-handed just by pure choice. But we could have had our Z-axis pointing the other way and it would have been completely fine. >> It's the same. >> It's the same. >> It's just this orientation. So, so we

38:36can't really use physics, right? And and to to illustrate this further, right? Let's think about what happens to like motions of particles and vectors in a mirror world. >> Okay. Okay. So, if I have a mirror that's right in front of me and I have a particle that's moving away from me. Yes. >> I would I would go to the other the other photo. >> Yes. If I have a if I have a if I have a mirror in front of me and I would go let's let's say the particle is going towards the mirror. >> Okay. >> Okay. So it's moving away from me. >> Yes. >> In the mirror world what I'm seeing is the particle would come towards me. >> Yes. >> Yes.

39:16>> Yes. >> So so the the trajectory of the particle is flipped.